I guess we get to choose what kind of grass and make our own estimate of "how many blades of grass per square centimeter".

A centimeter is relatively small. My own guess is that there wouldn't be more than, say, 20 blades of grass per square centimeter. I suppose if a person didn't like this estimate they could go out and COUNT how many blades of THEIR grass could fit into a square centimeter.

Now, 5 meters are 500 centimeters.

And 4 meters are 400 centimeters.

And there are supposedly 20 blades of grass per square centimeter.

20 * 400 * 500 = 4,000,000 - four million blades of grass for a 4m by 5m area.

Quite a few!

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